A Method and Criterion for Repetitive Surge Current in Silicon Carbide Schottky Diodes

The need for efficient power-conversion systems in renewable energy, electric vehicles, and industrial power applications has motivated the development of wide-bandgap power semiconductor devices, such as the SiC Schottky diode. An important parameter that establishes the reliability of these high-power devices is their repetitive forward surge current, which ensures robust circuit designs that can withstand high current conditions without damage or failure. However, there is no consistent measurement method to determine this parameter for SiC Schottky diodes, and manufacturers that provide this parameter have no clear indication of the methodology used to obtain the presented value. In this work, we propose a measurement method and a user-focused criterion for the repetitive peak forward surge current, which also ensures the junction temperature does not exceed the maximum device rating. We demonstrate the need for this criterion by comparing measured surge-current performance of commercially available diodes with two different structures—merged PN Schottky diodes and homogenous Schottky-barrier diodes—designed with three different blocking voltages: 650 V, 1200 V, and 1700 V.